The invention relates generally to semiconductor structures. More particularly, the invention relates to a semiconductor structure incorporating deep trench capacitors within an underlying first substrate, for access by logic circuits in a second substrate.
Trench capacitors can be used as decoupling elements or as memory elements in semiconductor structures. With traditional embedded dynamic random access memory (DRAM), in which deep trenches may be used as memory elements, a DRAM structure and a logic area must each be fabricated separately. Each of the DRAM structure and the logic area must be protected, for example, by a mask, during fabrication of the other. As semiconductor technology improves and integration density is increased, manufacture becomes more difficult. Additionally, the formation of deep trench capacitors adds cycle time to the wafer fabrication process, and can increase the number of defects that result from subjecting a substrate having logic circuits to the trench capacitor formation process.